Definitions

primary source

[prahym-er-ee sawrs, sohrs] / ˈpraɪm ɛr i ˈsɔrs, ˈsoʊrs /

NOUN

text, account, source others are based on

Synonyms

STRONG

eyewitness eyewitness account first-hand first-hand account first-hand report horse's mouth immediate source on-the-scene report on-the-scene reporter original account original source original text source text text of origin unmediated account

WEAK

observer witness

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

primary source

In the fourth quintile, Social Security is no longer the primary source of income, with income from pensions and retirement savings taking over the lead.

From MarketWatch ● Sep. 2, 2026

The staffer said that examiners were no longer allowed to access the primary source level data and could only “check the checker now,” meaning they must rely on a company’s own findings.

From Salon ● Sep. 1, 2026

Nectar supplies mostly sugar, while pollen is their primary source of protein.

From Science Daily ● Aug. 19, 2026

They added that most threats now emerge online, replacing handwritten letters and other traditional forms of communication as the primary source.

From BBC ● Jul. 23, 2026

Researchers also learned that the primary source of wound infection was not air, but contact with hands, instruments, and even drops from a surgeon's mouth and nose.

From "Ambushed!" by Gail Jarrow